Pinch valve element for plumbing fixture flush valve

ABSTRACT

The present invention discloses a pinch valve for replacing a diaphragm valve in a plumbing fixture. The plumbing fixture includes an inlet chamber defining a fluid inlet and in fluid communication with an inside chamber defining a fluid outlet. The pinch valve includes a cartridge member with a fluid inlet opening, a fluid outlet opening and a cartridge chamber defined by a cartridge chamber wall and in fluid communication with the fluid inlet opening and the fluid outlet opening. A flexible sealing member is positioned at least partially within the cartridge chamber and includes a wall with an inner surface defining an inner chamber and an outer surface defining an outer chamber between the outer surface of the flexible sealing member wall and the cartridge chamber wall. The inlet chamber of the plumbing fixture is in fluid communication with the inner chamber and the outer chamber.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 10/674,895 filed Sep. 29, 2003 now U.S. Pat. No.6,959,905.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to flush valves used inconnection with plumbing fixtures, such as toilets, urinals and thelike, and in particular, to a replacement for a diaphragm valve in sucha plumbing fixture.

2. Description of Related Art

Valves are used throughout many fluid transfer systems and in variousapplications, such as in the transfer and control of water conduitsystems, and in particular in connection with plumbing fixtures in bothresidential and commercial settings. For example, flush valves aretypically used for control and operation of toilets, urinals and thelike, such that when a user actuates a handle, water flows through theflush valve into a basin portion and out the drain.

Presently, a common type of flush valve is a diaphragm flush valve. Forexample, such a diaphragm flush valve is disclosed in U.S. Pat. No.4,327,891 to Allen et al. The Allen patent discloses the use of adiaphragm in a flush valve, where the diaphragm is made of molded rubberand serves to effectuate the flow of water from a water inlet, throughthe valve and to a water outlet. Further, the Allen patent sets forththe various components and sub-components of the flush valve accordingto the prior art.

Such diaphragm flush valves have several drawbacks. For example, therelatively small seal area in the diaphragm can become clogged withdebris, which causes the flush valve to remain open, resulting inconstant water flow. In addition, since the flush valve is pressurized,a small bleed hole is used in order to allow enough volume to flowthrough the valve in order to flush the toilet or urinal. This smallbleed hole is easily clogged, which can also result in the malfunctionof the valve. Still further, the flushing cycle of the diaphragm flushvalve takes approximately seven seconds to complete, depending upon theflow rates and water pressure entering the valve, due to the design ofthe diaphragm of the flush valve. Since an upper chamber fills slowly,the valve is slowly “shutting off”. Therefore, a significant amount ofwater is wasted through the trap and sewer line during the sealingprocess. The trip lever seal area can also be blocked with debris, whichcauses the valve to flow continuously. Yet another drawback is thatconventional diaphragm flush valves only work at water pressures greaterthan 35 psi, which is due to the difference in the diaphragm surfacearea and the diameter of the bleed hole.

Pinch valves have found use in various valve applications other than adiaphragm-type valve. For example, U.S. Pat. No. 4,111,391 to Pilolladiscloses a pinch valve including a distortable rubber-like valve memberin a generally cylindrical form. As disclosed in the Pilolla patent, thevalve member has uniformly spaced projections and grooves enabling it tocollapse upon itself and form a complete closure between opposite ends.Heretofore, however, the use of such a pinch valve as a replacementvalve in the application of flush valves for plumbing fixtures has notbeen effective due to the different sealing arrangement bound in pinchvalves in comparison to diaphragm valves. Therefore, there remains aneed for an effective valve for replacing a diaphragm flush valve in aplumbing fixture.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a valve replacementfor a diaphragm valve that overcomes the deficiencies of the prior art.It is another object of the present invention to provide a valvereplacement for a diaphragm valve that has a decreased failure rate and,therefore, an increased cost efficiency. It is a further object of thepresent invention to provide a valve replacement for a diaphragm valvethat has a larger seal area, such that small debris cannot be trapped inthe seal area and hold the valve open. It is a still further object ofthe present invention to provide a valve replacement for a diaphragmvalve that has a decreased flush time with a high flow rate andvelocity, thereby being more water efficient. It is yet another objectof the present invention to provide a valve replacement for a diaphragmvalve that is capable of resetting at low pressure, such as when afacility loses mainline pressure.

The present invention is directed to a pinch valve for use in a plumbingfixture, and is particularly adapted for replacement of a diaphragmvalve in a plumbing fixture. The plumbing fixture includes an inletchamber defining a fluid inlet, which is in fluid communication with aninternal chamber defining a fluid outlet. The pinch valve includes acartridge member having a fluid inlet opening, a fluid outlet openingand a cartridge chamber defined by a cartridge chamber wall. Thecartridge chamber is in fluid communication with the fluid inlet openingand the fluid outlet opening. A flexible sealing member is positioned atleast partially within the cartridge chamber and has a wall with aninner surface defining a flow chamber and an outer surface defining apressure chamber between the outer surface of the flexible sealingmember wall and the cartridge chamber wall. The inlet chamber of theplumbing fixture is in fluid communication with the flow chamber and thepressure chamber.

In an undisturbed state, fluid force in the pressure chamber is at leastequal to fluid force in the flow chamber. In this situation, the wall ofthe flexible member constricts inwardly and pinches, thereby preventingfluid flow through the flow chamber. However, when the pressure chamberis relieved of pressure, the fluid force in the pressure chamber is lessthan the fluid force in the flow chamber. When this occurs, the wallcollapses to an unpinched position, thereby permitting fluid flowthrough the flow chamber and causing water to flow through the flushvalve for flushing of the fixture.

The present invention is also directed to a plumbing fixture. Theplumbing fixture includes an inlet chamber defining a fluid inlet influid communication with an internal chamber defining a fluid outlet.The plumbing fixture also includes a pinch valve having a cartridgemember with a fluid inlet opening, a fluid outlet opening and acartridge chamber defined by a cartridge chamber wall and in fluidcommunication with the fluid inlet opening and the fluid outlet opening.The pinch valve further includes a flexible sealing member positioned atleast partially within the cartridge chamber and having a wall with aninner surface defining a flow chamber and an outer surface defining apressure chamber between the outer surface of the flexible sealingmember wall and a cartridge chamber wall. The inlet chamber of theplumbing fixture is in fluid communication with the flow chamber and thepressure chamber as described above.

The present invention, both as to its construction and its method ofoperation, together with the additional objects and advantages thereof,will best be understood from the following description of exemplaryembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional elevational view of a diaphragm flush valveaccording to the prior art;

FIG. 2 is a cross-sectional elevational view of a flush valveincorporating a pinch valve element in accordance with the presentinvention;

FIG. 3 is an exploded perspective view of the flush valve including thepinch valve element of FIG. 2;

FIG. 4 is an exploded perspective view of the pinch valve replacementelement of FIG. 2;

FIG. 5 is a cross-sectional view of the pinch valve replacement elementof FIG. 2;

FIG. 6A is a cross-sectional view taken along lines 6—6 of FIG. 5 shownin an collapsed unsealed position, while FIG. 6B is a similarcross-sectional view shown in a pinched or constricted sealing position;

FIG. 7 is a detailed sectional view of a seal portion of the pinch valveelement of FIG. 5;

FIG. 8 is a side cross-sectional view of a pinch valve replacementelement shown in an alternative embodiment;

FIG. 9 is a cross-sectional view of a flush valve incorporating a pinchvalve element in a further embodiment of the present invention showingan alternative activation mechanism;

FIG. 10 is a cross-sectional view of a flush valve incorporating a pinchvalve element in yet a further embodiment of the present inventionshowing a pressurizing unit for valve control; and

FIG. 11 is a cross-sectional view of a flush valve incorporating a pinchvalve element in a further embodiment of the present inventionincorporating an external pressurizing source.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to flush valves, and in particular to animproved valve insert for use in such valves. The valve insert isparticularly useful for replacement of a traditional diaphragm-typevalve insert for flush valves. Such traditional diaphragm-type valvesare shown in U.S. Pat. No. 4,327,891, as depicted in FIG. 1 herein. Insuch diaphragm-type flush valves, the flush valve 2 has a general hollowbody 10 which includes an inlet connection 12, an outlet connection 15and a handle coupling connection 16. The top of the valve body is closedby an outer cover 18 and an inner cover 20. The inlet portion of thevalve is separated from the outlet portion by a central throat 22 whichis attached to the inside walls of the valve body 10. A main valve seat24 is formed on the top of the throat.

The valve is actuated by an operating handle 26 which is fastened to thevalve body 10 by means of coupling nut 28. The handle is connected to aplunger 30 which extends to the interior portion of the valve body. Theplunger 30 is guided and supported by a bushing 32 and restored by aspring 34. A rubber sealing cap or packing 36 is snapped on the end ofbushing 32 and prevents leakage outward from the handle opening.

The annular valve seat 24 is normally closed by a diaphragm 38. Thediaphragm extends across the body 10 and defines an upper chamber 40.The diaphragm has a by-pass 42 which provides fluid communicationbetween the inlet side of the valve and the upper chamber 40. A filter44 may be provided to prevent clogging of the by-pass 42.

The diaphragm 38 is attached at its outer edge to the valve body. Theouter cover 18 clamps the diaphragm between a shoulder on the valve bodyand the inner cover 20. The center of the diaphragm has an opening whichallows fluid communication between the upper chamber 40 and the outlet14. A relief valve shown generally at 46 is attached to the diaphragmand normally closes the opening at the center of the diaphragm. Therelief valve 46 includes a guide portion 48 having wings 49. The wings49 fit closely against the inside diameter of the throat 22. The guide48 also has a lip 50. The lip supports a collar 52. The relief valve 46includes a clamping member 54 which is threadedly engaged with the guideportion 48. The clamping member 54 clamps the inner edge of thediaphragm 38 between the member 54 and the collar 52. The clampingmember 54 has a hole in the middle which is normally closed by anauxiliary valve member 56. This member is connected to a depending stem58 which extends to a point opposite the actuating plunger 30. Theclamping member 54 may have a rubber liner to improve the sealingcontact between the auxiliary valve member 56 and the clamping member.

The operation of this prior art valve is as follows. In thenormally-closed position shown in FIG. 1, water pressure at the valveinlet is communicated to the upper chamber 40 through the by-pass 42.Since the surface area subjected to the water pressure is greater on theupper side of the diaphragm, the water pressure forces the diaphragmdown onto the valve seat 24. This prevents water from flowing to theoutlet 14. When a user rotates the handle 26 in any direction theplunger 30 moves inwardly, tilting the stem 58 and moving the auxiliaryvalve member 56 out of the sealing engagement with the clamping member54. This relieves the pressure in the upper chamber 40 by allowing waterto flow through the guide member 48. With the upper chamber pressurerelieved the inlet water pressure forces the diaphragm upwardly, off ofthe main valve seat 24. Water then flows directly from the inlet,through the throat 22 and to the outlet 14. When the diaphragm 38 andrelief valve 46 move upwardly the auxiliary member 56 reseats, closingoff the upper chamber, forcing the diaphragm back onto the main valveseat 24 to close the valve 46. The guide 48 and its associated wings 49contact the throat 22 to provide stability to the diaphragm as it moves.The guide keeps the diaphragm level as it closes and thus preventschattering. Should the operating lever 26 be held overly long, the valve46 will still operate as the stem 58 has a telescoping part which willallow it to return to its normal position even though obstructed by theplunger 30.

As discussed in detail hereinabove, flush valves incorporating such adiaphragm 38 have numerous drawbacks and other deficiencies.

Accordingly, the present invention is directed to a valve element as areplacement for the diaphragm in a conventional valve body. Moreparticularly, with specific reference to FIGS. 2–8, the valve element ofthe present invention includes a pinch valve replacement element 100which is provided for use with a conventional flush valve body such aspreviously described in terms of the prior art including flush valve 2′,a hollow body 10′, an inlet connection 12′, an outlet connection 14′,and a handle coupling connection 16′. In the present invention, pinchvalve replacement element 100 replaces the diaphragm valve mechanismused in prior art valve bodies, and as such sits directly within hollowbody 10′ on main valve seat 24′ in direct communication with centralthroat 22′, providing a mechanism for regulating water flow through thevalve body by way of central throat 22′, as will be discussed in moredetail herein.

Pinch valve replacement element 100 generally includes a cylindricalcartridge member 102 and a dynamic pinch-type flexible sealing member130 provided within the cartridge member 102. Cartridge member 102 isdefined by a tubular cartridge chamber wall 110 extending between afirst open end 102 forming a fluid inlet opening and a second open end104 forming a fluid outlet opening, and further defining an internalchamber 108 extending therethrough. The internal chamber 108 providesdirect fluid communication between the fluid inlet opening defined byfirst open end 104 and the fluid outlet opening defined by second openend 106. A fluid channel 120 extends through the cartridge chamber wall110, desirably at a position adjacent first open end 104. Such fluidchannel 120 includes a fluid inlet opening 122, which may be present onthe top surface of cartridge member 102 adjacent first open end 104thereof. Desirably, a plurality of fluid channels 120 are providedthrough the cartridge chamber wall 110 and may be spaced from eachother, such as depicted in FIGS. 6A–6B.

The fluid inlet opening preferably has a diameter which is less than thediameter of the fluid inlet established through fluid channel 156 ofupper clamping member 150. In use, this fluid channel 120 provides amechanism for fluid flow from the upper chamber 40′ of the valve bodyinto the pinch valve replacement element 100, which fluid flow regulatessealing of the valve for operation of the valve, as will be described inmore detail herein. Fluid channel 120 may further be provided with afilter device (not shown) which prevents solid or semi-solid materialfrom flowing through or clogging the fluid channel 120.

The pinch valve replacement element 100 further includes a flexiblesealing member 130 positioned within the internal chamber 108 of thecartridge member 102. The flexible sealing member 130 includes aflexible tubular wall 132 extending between a first open end 132positioned adjacent first open end 104 of cartridge member 102, and asecond open end 134 positioned adjacent second open end 106 of cartridgemember 102. As such, the flexible sealing member 130 is positioned atleast partially within the cartridge member 108, and extendssubstantially between first open end 104 and second open end 106 ofcartridge member 102.

More particularly, the first open end 134 of the flexible sealing member130 is fixed upon an upper annular rim 112 defined within the first openend 104 of the cartridge member 102. In a similar manner, the secondopen end 136 of the flexible sealing member 130 is fixed upon a lowerannular rim 114 defined within the second open end 106 of the cartridgemember 102. Any means of affixing the ends of the flexible sealingmember 130 to the ends of the cartridge member 102 may be employed.Desirably, this is accomplished through a mechanical securement, such asthrough upper clamping member 150 and lower clamping member 160, as bestdepicted in FIGS. 4 and 5.

Upper clamping member 150 desirably includes a generally disc-shapedcylindrical body extending between an upper, external surface 152 and alower, internal surface 154, with an internal fluid channel 156extending therethrough. The outer cylindrical surface of upper clampingmember 150 is threaded with external threads 158 for threaded engagementwith internal threads 105 which extend within the inner surface of firstopen end 104 of cartridge member 102. By threading such external threads158 of upper clamping member 150 with the internal threads 105 ofcartridge member 102, the first open end 134 of the flexible sealingmember 130 can be effectively trapped between the internal surface 154of upper clamping member 150 and the upper annular rim 112 of cartridgemember 102, thereby effectively securing the entire annular rim of thefirst open end 134 of flexible sealing member 130 therebetween. In asimilar manner, lower clamping member 160 desirably includes a generallydisc-shaped cylindrical body extending between a lower, external surface162 and an upper, internal surface 164, with an internal fluid channel166 extending therethrough. The outer cylindrical surface of lowerclamping member 150 is threaded with external threads 168 for threadedengagement with internal threads 107 which extend within the innersurface of second open end 106 of cartridge member 102. By threadingsuch external threads 168 of lower clamping member 160 with the internalthreads 107 of cartridge member 102, the second open end 134 of theflexible sealing member 130 can be effectively trapped between theinternal surface 164 of lower clamping member 160 and the lower annularrim 114 of cartridge member 102, thereby effectively securing the entireannular rim of the second open end 136 of flexible sealing member 130therebetween. As such, both of the ends 134, 136 of the flexible sealingmember 130 are statically sealed with respect to cartridge member 102.Cartridge member 102 and upper and lower clamping members 150, 160 maybe constructed of any rigid material, for example a metallic materialsuch as stainless steel, or a rigid polymeric material, such aspolyethylene terephthalate.

With upper clamping member 150 and lower clamping member 160 secured toopposing ends of cartridge member 102, fluid channel 156 of upperclamping member 150 defines an inlet opening for fluid flow intocartridge chamber 108, and fluid channel 166 of lower clamping member160 defines an outlet opening for fluid flow out of cartridge chamber108, as will be discussed in more detail herein.

Moreover, with flexible sealing member 130 secured as such withincartridge member 102, the tubular wall 132 separates cartridge chamber108 into two separate chambers. In particular, a first chamber isprovided as pressure chamber 142, defined between the inner wall surfaceof cartridge chamber wall 110 and the outer wall surface 140 of tubularwall 132 of flexible sealing member 130. A path for fluid flow betweenthis pressure chamber 142 and the external area of the pinch valvereplacement element 100 (namely, upper chamber 40′ of the valve body) isprovided through the fluid channel 120 which extends through thecartridge chamber wall 110 of cartridge chamber 102 adjacent the firstopen end 104 thereof. A second chamber is provided as flow chamber 144,defined as the interior chamber within inner wall surface 138 of tubularwall 132 of flexible sealing member 130. The fluid channels 156, 166 ofupper clamping members 150, 160 are in fluid communication with thisflow chamber 144. As will be discussed in more detail herein, fluid flowthrough the pinch valve replacement element 100, and therefore fluidflow through the valve body itself, is regulated by the fluid pressurewithin pressure chamber 142 which regulates the pinching or collapsingof the flexible sealing member 130 to close or open this flow chamber144, thereby regulating fluid flow between fluid channel 156 and fluidchannel 166.

The flexible sealing member 130 is constructed of an elastomericmaterial, such as rubber, a polymeric material or other syntheticmaterial having elastomeric properties. Further, in order to reduce thechances of failure and reduce the costs of maintenance, a portion or allof the walls of the flexible sealing member 130 may be reinforced with asemi-rigid material. Flexible sealing member 130 is moveable between acollapsed state as shown in FIG. 6A, in which the tubular wall 132 iscollapsed, defining flow chamber 144 therein, and a constricted orpinched state as shown in FIG. 6B, in which the tubular wall 132 ispinched or gathered to form a closed structure in which flow chamber 144is entirely closed off. In particular, flexible sealing member 130 iscapable of folding to form a plurality of folded walls which mate witheach other and meet together at the center of the pinched sleeve to forma generally complete closure. This folding may be assisted by providinga plurality of grooves 148 on the outer wall surface 140 to act as aweakened portion of tubular wall 132 of flexible sealing member 130.Desirably, three grooves 148 are provided such that flexible sealingmember 130 pinches off to form three pairs of mating wall structureswhich meet at a center point, closing off flow chamber 144. It iscontemplated that the inner wall surface 138 of tubular wall 132 mayinclude protrusions at a point corresponding to each of grooves 148 suchthat, upon pinching off, the protrusions meet at a center point toensure complete closing of flow chamber 144.

Pinch valve replacement element 100 is positioned within the hollow body10′ of the flush valve 2′, and in particular, within central throat 22′.The cylindrical shape of the cartridge member 102 is dimensioned suchthat cartridge chamber wall 110 has an outer diameter which issubstantially the same size, or only slightly smaller than, the internaldiameter of central throat 22′, such that a snug fit is achieved withlittle or no annular space therebetween. The cartridge member 102 mayalso include a rim portion 116 with a rim portion undersurface 118. Therim portion undersurface 118 is sized and shaped so as to engage withand form a seal with the upper edge defining the main valve seat 24′ ofthe central throat 22′ of the plumbing fixture. For example, theundersurface 118 of the rim portion 116 may include a layer capable offorming a seal, desirably an elastomeric layer or other layer such as acoated layer, a bonded layer, or other similar seal area.

Cartridge member 102 further includes a plunger channel 124 extendingthrough the cartridge chamber wall 110 at a location between the upperannular rim 112 within first open end 104 and the lower annular rim 114within second open end 106. In this manner, plunger channel 124establishes a path for fluid flow between pressure chamber 142 and theexternal environment, namely outlet connection 14′, through thecartridge wall 110. When pinch valve replacement element 100 ispositioned within central throat 22′ of the flush valve body, the lowerend of the cartridge member 102 adjacent second open end 106 must beproperly positioned such that the plunger channel 124 is aligned withplunger 30′, which is interconnected with operating handle 26′ andextends through hollow body 10′ through coupling nut 28′, bushing 32′,spring 34′ and packing 36′ as described above in connection with FIG. 1with reference to the prior art. Desirably, plunger 30′ may bepositioned so as to extend slightly within plunger channel 124, whichextends through cartridge chamber wall 110. As such, plunger channel 124is desirably larger in diameter than plunger 30′ to provide slidingmovement of plunger 30′ therein and to permit fluid to flow aroundplunger 30′ through plunger channel 124.

Moreover, plunger channel 124 includes a sealing member, and preferablya spherical sealing member such as ball seal 180, for closing fluidchannel 120 to prevent fluid flow therethrough. Desirably, such asealing member is a ball seal 180 positioned within pressure chamber 142and adapted to seal against the inner surface of the cartridge chamberwall 110 at the interior opening forming plunger channel 124, as shownin FIG. 5. This sealing member may be constructed of any materialcapable of sealing fluid channel 120 for fluid flow, and is desirably anelastomeric material such as rubber. It is also contemplated thatplunger 30′ may be provided with an enlarged end surface to act as sucha sealing member. Also, in embodiments wherein pinch valve replacementelement 100 is provided as an integral unit for replacement of adiaphragm-type valve element for retrofitting an existing flush valve, aseparate extension piece can be provided for attachment to the end ofplunger 30′ so as to extend within plunger channel 124 and seal off theopening and prevent fluid flow therethrough.

Assembly of flush valve 2′ including pinch valve replacement element 100is as follows. Flush valve 2′ is provided with hollow body 10′, and maybe appropriately connected to a water source through inlet connection12′, and to a plumbing fixture such as a toilet, a urinal, or the like,through outlet connection 14′. Also, operating handle 26′, as well asthe corresponding plunger 30′, bushing 32′, spring 34′ and packing 36′components, may be connected to handle coupling connection 16′ throughcoupling nut 28′. Pinch valve replacement element 100 is provided withincentral throat 22′, with rim portion 116 resting on main valve seat 24′in a sealing engagement. Pinch valve replacement element 100 ispositioned such that plunger channel 124 is aligned with plunger 30′,and desirably, such that plunger 30′ slightly extends within plungerchannel 124. Inner cover 20′, if provided, may then be placed over flushvalve 2′, with outer cover 18′ thereafter threaded onto hollow body 10′to enclose flush valve 2′. In this manner, pinch valve replacementelement 100 provides a valve element for regulating fluid flow, inparticular water flow, between inlet connection 12′ and outletconnection 14′.

As noted, the present invention is directed to a flush valve includingthe pinch valve element therein, as well as to the pinch valve elementfor use as a replacement or retrofit for a diaphragm-type valve.Accordingly, in use as a replacement or retrofit application, assemblyof the flush valve 2′ may first involve removing the outer and innercovers, and removing a diaphragm-type valve, such as the diaphragm 38and all corresponding parts described in connection with the prior artwith reference to FIG. 1. After removal of such diaphragm parts, thepinch valve replacement element 100 can be placed within the centralthroat 22′ of hollow body 10′ as described above, with plunger 30′aligned with plunger channel 124, and with the inner and outer covers20′, 18′ replaced onto hollow body 10′.

In operation, flush valve 2′ including pinch valve replacement element100 therein is connected to an appropriate source of water through inletconnection 12′ and to an appropriate fixture through outlet connection14′. Pinch valve replacement element 100 is sealed off because flexiblesealing member 130 is pinched. This is achieved by the fluid force inthe pressure chamber 142 being at least equal to the fluid force in theflow chamber 144. In particular, water flows into upper chamber 40′ offlush valve 2′ from inlet connection 12′, and passes into fluid inletopening 122 and through fluid channel 120 into pressure chamber 142.When sufficient water is present within pressure chamber 142, theflexible tubular wall 132 of flexible sealing member 130 pinches and/orfolds along grooves 148, closing off flow chamber 144 and forming aclosed structure as seen in FIG. 6B. In this state, the tubular wall 132of the flexible sealing member 130 folds inwardly and pinches the innerwall surface 138 of the flexible sealing member 138 against itself.Accordingly, this prevents fluid flow through the flow chamber 144.

To operate the valve, i.e., to provide water to the fixture, water flowmust be established through cartridge chamber 108, which is dynamicallysealed off through flexible sealing member 138 as described above.Accordingly, the pressure which forces flexible sealing member 138pinched closed must be relieved. This is achieved by activation of theoperating handle 26′ of the flush valve 2′. More particularly,rotational movement of operating handle 26′ in any direction causes theplunger 30′ to moves inwardly. Such movement causes the end of plunger30′ to pass through plunger channel 124 and to contact and displace ballseal 180 from sealing engagement with plunger channel 124. As such,water flows from within the pressure chamber 142 through the plungerchannel 124 and out through outlet connection 14′ to the plumbingfixture connected thereto. This outflow of water from within thepressure chamber 142 relieves the pressure within the pressure chamber142, which reduces the fluid force in the pressure chamber 142 to lessthan the fluid force in the flow chamber 144. With this reduction inpressure, tubular wall 132 of the flexible sealing member 130 relaxes orcollapses to an unpinched position, thereby permitting fluid flowthrough the flow chamber 144. As such, water is then free to flowdirectly from the inlet 12′, through upper chamber 40′, and down throughthe cartridge chamber 108, more particularly down through fluid channel156, through flow chamber 144, out through fluid channel 166 and to theoutlet 14′ for delivery to the associated plumbing fixture.

Plunger channel 124 cannot remain permanently open or sufficientpressure cannot build in the pressure chamber 142. Accordingly, duringthis water flow through flush valve 2′, sufficient water passes throughthe flush valve 2′ through cartridge chamber 108 to flush the fixture,while water is simultaneously passing through fluid inlet opening 122and through fluid channel 120 into pressure chamber 142. This flow ofwater into pressure chamber 142 gradually increases the fluid pressurewithin pressure chamber 142, and causes, the sealing member, which isprovided for example through ball seal 180, to re-engage and re-seal theopening to plunger channel 124 to prevent any further fluid flowtherethrough. When the plunger channel 124 is sealed by the ball seal180 as such, fluid can collect in the pressure chamber 142 at a morerapid pace. As such, the fluid force within pressure chamber 142increases to a level at which it is greater than the fluid force withinflow chamber 144. At this point, tubular wall 132 of flexible sealingmember 130 once again constricts or pinches, thereby closing off flowchamber 144 from further fluid flow therethrough.

As noted, when the seal between the ball seal 180 and the plungerchannel 124 is disengaged or broken, the ball seal 180 must bere-engaged with the plunger channel 124 in order to stop the fixturefrom running continuously. There are several manners of accomplishingthis result. For example, a sloped surface 186 may be providedimmediately adjacent and be sloped toward the inner wall opening atplunger channel 124. In this manner, when the plunger 30′ pushes anddisengages the ball seal 180, and after the fluid is finished exitingthrough the plunger channel 124, the ball seal 180 slides or rolls backdown the sloped surface 186 and to re-engage with the opening at plungerchannel 124.

As indicated, pinch valve replacement element 100 can be provided as anintegral unit with flexible sealing member 130 secured within cartridgemember 102 as described. In this manner, the pinch valve replacementmember 100 can be easily inserted into the central throat 22′ of hollowbody 10 of a flush valve body, and serves as an easy replacement for aremoved diaphragm valve element. Accordingly, the present invention isdirected not only to a pinch valve as described hereinabove, but also toa plumbing fixture, such as a flush valve assembly, which includes sucha pinch valve in combination with a flush valve assembly.

FIG. 8 depicts a pinch valve replacement element 200 in a furtherembodiment of the present invention. In particular, in the embodimentdepicted in FIG. 8, the cartridge member is substantially identical tothe previously described embodiment, with the exception that the fluidchannel does not extend through the cartridge chamber wall. Instead, inthe present embodiment, a different type of upper clamping member 250 isprovided for securing the flexible sealing member within the cartridgemember, which upper clamping member 250 includes a fluid channel 220including a fluid inlet opening 222. Also, the flexible sealing memberincludes a bleed hole 226 extending through the wall thereof at aposition adjacent and aligned with the fluid channel 220. The pinchvalve replacement element 200 works in a similar manner as in theprevious embodiment, except that in order for the flexible sealingmember to constrict and pinch the valve closed, water enters into thepressure chamber through the upper clamping member 250 as opposed tothrough the cartridge chamber wall of the cartridge chamber, that is,through the fluid inlet opening 222, through the fluid channel 220, andthrough the bleed hole 226, as shown in FIG. 8. It is noted that aplurality of fluid channels 220 may be provided through the upperclamping member, and may be properly spaced thereabout.

FIG. 9 depicts a further embodiment of the present invention, in whichthe mechanical activation mechanism for the flush valve is substitutedor replaced with an electronic activation mechanism, such as a solenoidmechanism. In particular, in the embodiment of FIG. 9, the flush valve2′ including the pinch valve replacement element 100 is identical to theembodiment described in connection with FIGS. 1–7, but substituting thepreviously described operating handle with a solenoid assembly 190.Solenoid assembly 190 may be any assembly capable of providing a linearmovement upon activation, as is known in the art. Upon activation,solenoid assembly 190 causes a linear movement of plunger 30′, which inturn causes activation of the pinch valve assembly for water flowthrough the flush valve for flushing of the fixture, as previouslydescribed. Activation of the solenoid assembly may be accomplished inany known manner, such as through contact with a push button 192 whichactivates the solenoid assembly 190. Alternatively, an electronic sensorassembly (not shown) may be associated with solenoid assembly 190 tocause automatic activation thereof, as is known in the art.

FIG. 10 depicts a further variation on the embodiment of FIG. 9, withthe solenoid element acting as a flow regulator as opposed to merelyproviding a linear actuator for activation of a plunger element. Moreparticularly, as with the embodiment of FIG. 9, the flush valve 2′including the pinch valve replacement element 100 is identical to theembodiment described in connection with FIGS. 1–7, but substituting thepreviously described operating handle with a solenoid assembly 390 andeliminating the need for a ball seal. Instead, sealing of the pressurechamber 142 is achieved through water flow through the solenoid assembly390.

For example, the solenoid assembly 390 may be interconnected to thepinch valve replacement element 100 through a flow channel 394 extendingthrough the cartridge wall 110, thereby establishing fluid communicationbetween pressure chamber 142 and the solenoid assembly 390. Solenoidassembly 390 includes a housing which defines an interior flow chamber391 therein, with a flow port 392 extending through the housing andproviding a path for fluid communication between the interior flowchamber 391 and outlet 14′, and with flow channel 394 in fluidcommunication with interior flow chamber 391. Solenoid assembly 390further includes a solenoid coil 393 which surrounds a plunger 395biased by spring 396 to the right, as illustrated in the drawings, ortoward a position closing the flow port 392. The solenoid assembly 390is attached to the valve body 10′ through a coupling nut 28′, and isinterconnected with pinch valve replacement element 100 through a tubingsuch as flow channel 394. Solenoid assembly 390 may further beinterconnected with an electronic sensor element for activation thereof.

In operation, the plunger 395 is biased through spring 396 to a positionclosing and sealing flow port 392. In this position, a sealedenvironment is established such that pressure chamber 142 can fill withwater as described previously, thereby constricting flexible wall 132 offlexible sealing member 130 and closing or pinching off the flow chamber144. When the solenoid assembly 390 is activated, such as through aninfrared sensor (not shown), electric power is applied to the solenoidcoil 393, causing the plunger 395 to move away from flow port 392. Waterwhich is contained within pressure chamber 142 is then released and canthen flow through flow channel 394 into interior flow chamber 391 andout through flow port 392 where it is released into outlet 14′. Thisreleases the pressure within pressure chamber 142 which in turn causesthe flexible wall 132 of flexible sealing member 130 to collapse,thereby opening flow chamber 144 and permitting water flow therethrough.

After the solenoid assembly 390 has been activated for a predeterminedtime period, such as five seconds, the electric power to the solenoidcoil 393 is cut off, and the spring 396 with again bias plunger 395against flow port 392, thereby closing it off and sealing off interiorflow chamber 391. Pressure can then accumulate therein, and water willagain flow through fluid inlet opening 122 and fluid channel 120 intopressure chamber 142, and will once again pinch off flow chamber 144when sufficient pressure is established to constrict flexible wall 132.

FIG. 11 depicts yet a further embodiment of the present invention, inwhich the pinch valve replacement element 400 includes a pressurechamber 442 which is designed to be pressurized through an external airsource as opposed to water flowing through the flush valve. Moreparticularly, the activation mechanism of the previously describedembodiment of FIG. 1–7 is replaced with an activation mechanismincluding a pressure source P. Cartridge wall 410 does not include anyfluid channel extending therethrough, nor any plunger channel extendingtherethrough. Instead, an air channel 494 extends from pressure source Pthrough the cartridge wall 410 and into pressure chamber 442.Pressurized air can therefore be provided from pressure source P throughair channel 494 and into pressure chamber 442. When the air pressurewithin pressure chamber 442 is sufficient, flexible wall 132 of flexiblesealing member 130 constricts to pinch off the flow chamber 144. Toactivate the valve, an activation mechanism, such as push button 492,causes the pressure source P to release the air pressure provided withinpressure chamber 442, such as through an air bleed hole (not shown).This causes a decrease in the air pressure within pressure chamber 442,and once the pressure falls below a predetermined threshold, the waterpressure acting upon the flexible wall of flexible sealing member 130will overcome the air pressure and collapse flexible wall 132, therebyopening flow chamber 144 for water flow therethrough. After apredetermined period of time, pressure source P will once again provideair pressure through air channel 494 to re-pressurize pressure chamber442, which in turn will cause the flexible wall 132 of flexible sealingmember 130 to constrict and again pinch off flow chamber 144, stoppingthe flow of water therethrough. In such an embodiment, it is importantto ensure that pressure source P, as well as air channel 494 andpressure chamber 442, are appropriately sealed from both the externalenvironment as well as to the internal water flow within the valveassembly, so as to be able to maintain proper pressure regulationtherein and prevent water from entering the pressure source P.

The present invention provides a more durable flush valve requiring lessmaintenance through the use of the pinch valve element as opposed to astandard conventional diaphragm-type valve. Due to the large seal areaestablished by the wall 132 of the flexible sealing member 130 closingin on itself, even if debris is trapped or engaged in the pinched area,a seal is still realized. Also, the large diameter secondary fluid inletopening established by fluid channel 156 is not easily clogged. Inaddition, the present invention provides a valve element that has asingle static seal area as opposed to multiple sealing areas as in thediaphragm valve 12 according to the prior art.

The pinch valve replacement element 100 of the present invention iscapable of achieving flush flow-through times of about 3.5 seconds witha very high flow rate velocity when used in connection with a standardflush valve. Moreover, the pinch valve element is capable of being resetat very low fluid pressures, and therefore can reseal itself and closeoff water flow even when a facility loses mainline pressure.

This invention has been described with reference to the preferredembodiments. Various modifications and alterations will be apparent uponreading and understanding the preceding detailed description. It isintended that the invention be construed as including all suchmodifications and alterations.

1. A pinch valve for regulating fluid flow through a flush valveextending between a fluid inlet in connection with a source of fluid anda fluid outlet in connection with a plumbing fixture, the pinch valvecomprising: a cartridge member having a cartridge chamber wall extendingbetween a fluid inlet opening and a fluid outlet opening and defining acartridge chamber therebetween; a flexible sealing member positioned atleast partially within the cartridge chamber and having a flexible wallwith an inner surface defining a flow chamber extending between thefluid inlet opening and the fluid outlet opening of the cartridgemember, and an outer surface defining a pressure chamber between theouter surface of the flexible wall and the cartridge chamber wall,wherein the flexible wall is adapted to constrict upon itself when afluid force in the pressure chamber is at least equal to the fluid forcein the flow chamber to close the flow chamber and prevent fluid flowtherethrough; wherein the cartridge member comprises at least one fluidinlet channel extending therethrough and in fluid communication with thefluid inlet for fluid flow into the pressure chamber; and at least oneseparate fluid outlet channel extending therethrough and in fluidcommunication with the fluid outlet for fluid flow out of the pressurechamber, and said fluid outlet channel configured to be sealed toprevent fluid flow out of the pressure chamber.
 2. The pinch valve ofclaim 1, wherein when the pressure chamber is relieved of pressure, thefluid force in the pressure chamber is less than the fluid force in theflow chamber, such that the flexible wall collapses, thereby permittingfluid flow through the flow chamber.
 3. The pinch valve of claim 1,wherein the fluid inlet in connection with the source of fluid is influid communication with the flow chamber and the pressure chamber ofthe pinch valve.
 4. The pinch valve of claim 1, wherein the fluid inletchannel is a bleed opening having a diameter less than the diameter ofthe fluid inlet opening of the cartridge member.
 5. The pinch valve ofclaim 4, further comprising a filter in operative communication with thefluid inlet channel.
 6. The pinch valve of claim 1, wherein the fluidoutlet channel includes a sealing member for sealing engagement toprevent fluid flow out of the pressure chamber.
 7. The pinch valve ofclaim 6, wherein the plumbing fixture includes an actuation mechanism inoperative communication with the pressure chamber, such that actuationof the actuation mechanism relieves the pressure chamber of pressure,reducing the fluid force in the pressure chamber to less than the fluidforce in the flow chamber, such that the flexible wall of the flexiblesealing member collapses, thereby permitting fluid flow through the flowchamber.
 8. The pinch valve of claim 7, wherein the actuation mechanismincludes a plunger in operative communication with the fluid outletchannel such that when the actuation mechanism is actuated, the plungercauses the sealing member to displace from sealing engagement with thefluid outlet channel to permit fluid flow out of the pressure chamber.9. The pinch valve of claim 8, wherein the actuation mechanism furtherincludes a handle element extending externally from the plumbing fixtureand the plunger extends internally within the plumbing fixture and is inoperative communication with the handle element, such that, when thehandle element is actuated, the plunger is correspondingly actuated todisplace the sealing member.
 10. The pinch valve of claim 9, wherein thesealing member is a substantially spherical member configured tosealingly engage a corresponding opening in the fluid outlet channel.11. The pinch valve of claim 10, wherein the sealing member isconstructed from an elastomeric material.
 12. The pinch valve of claim1, wherein the cartridge member includes a rim portion having anundersurface configured to engage with an upper edge of an insidechamber of the plumbing fixture.
 13. The pinch valve of claim 1, whereinthe cartridge chamber is further defined by an upper annular rimadjacent the fluid inlet opening and a lower annular rim adjacent thefluid outlet opening, wherein the cartridge member further comprises anupper clamping member including a fluid channel extending therethroughand in fluid communication with the fluid inlet opening of the of thecartridge chamber, the upper clamping member configured to engage thecartridge chamber wall and abut the upper annular rim, and wherein thecartridge member further comprises a lower clamping member including afluid channel extending therethrough and in fluid communication with thefluid outlet opening of the cartridge chamber, the lower clamping memberconfigured to engage the cartridge chamber wall and abut the lowerannular rim.
 14. The pinch valve of claim 13, wherein at least a portionof a first end of the flexible sealing member is clamped between theupper clamping member and the upper annular rim and at least a portionof a second end of the flexible sealing member is removably clampedbetween the lower clamping member and the lower annular rim, therebysecurely positioning the flexible sealing member within the cartridgechamber.
 15. The pinch valve of claim 13, wherein the upper clampingmember and the lower clamping member are threadedly engaged withcorresponding threaded portions of the cartridge chamber wall.
 16. Aflush valve for a plumbing fixture comprising: a) an inlet chamber influid communication with a fluid source; b) an outlet chamber in fluidcommunication with a plumbing fixture; and c) a pinch valve forregulating fluid flow between the inlet chamber and the outlet chamber,said pinch valve comprising: a cartridge member having a cartridgechamber wall extending between a fluid inlet opening in fluidcommunication with the inlet chamber and a fluid outlet opening in fluidcommunication with the outlet chamber, the cartridge chamber walldefining a cartridge chamber therebetween; and a flexible sealing memberpositioned at least partially within the cartridge chamber and extendingbetween the fluid inlet opening and the fluid outlet opening of thecartridge member, the flexible sealing member having a flexible wallwith an inner surface defining a flow chamber extending between thefluid inlet opening and the fluid outlet opening of the cartridgemember, and an outer surface defining a pressure chamber between theouter surface of the flexible wall and the cartridge chamber wall,wherein the cartridge member further includes at least one fluid inletchannel for fluid flow from the inlet chamber into the pressure chamberand at least one separate fluid outlet channel for fluid flow from thepressure chamber to the outlet chamber, and said fluid outlet channelconfigured to be sealed to prevent fluid flow out of the pressurechamber, and wherein the flexible wall is adapted to constrict uponitself when a fluid force in the pressure chamber is at least equal tothe fluid force in the flow chamber to close the flow chamber andprevent fluid flow therethrough.
 17. The flush valve of claim 16,wherein when the pressure chamber is relieved of pressure, the fluidforce in the pressure chamber is less than the fluid force in the flowchamber, such that the flexible wall collapses, thereby permitting fluidflow through the flow chamber.
 18. The flush valve of claim 16, whereinthe fluid outlet channel includes a resettable sealing member operativefor movement between a sealed position for sealing engagement to preventfluid flow out of the pressure chamber, and an open position to permitfluid flow out of the pressure chamber, and resettable to the sealedposition.
 19. The flush valve of claim 18, wherein the inlet chamber isin fluid communication with the flow chamber through the fluid inletopening of the cartridge member and with the pressure chamber of thepinch valve through the fluid inlet channel of the cartridge member.